Well I tried feeding again tonite after only two days of being in the tub, and he hit it instantly! Result!
I have seen a little bit more of him since the move too, more confident to come out for a look around, I left the rat on the heater radiator next to his tub to warm and he was cruising around smelling it. I can't believe the difference , he is a different snake. Goes to show the value of the small tub, even though the viv I first put him in was less than 2ft.
He is still cruising around now? Hours later, is he still hungry ? Should you or can you feed two rats at one sitting??
Thanks to all for the positive advise, hints and tips!
Hopefully he will keep on eating regularly.